When preparing piping bags for pre-filling the bags are usually separated individually from e.g. a continuous web comprising numerous piping bags. The individual bag may then be filled, or strictly speaking pre-filled, with substances in a substantially viscous liquid or fluid form, e.g. foodstuffs, glue, cement, plaster; and subsequently sealed shut.
This operation is usually time consuming as one bag at a time must be separated from the web of piping bags and arranged such as to allow for the liquid to be filled in the individual piping bag.
WO 2007/081272 A1 discloses a pair of joined webs of sequentially disposed package blanks. The package blanks are held together by a continuous retaining means extending in a longitudinal direction of the web. The package blanks are fastened, at their respective first ends at the retaining means. The webs are joined to each other at the respective second ends of the package blanks. The package blanks may be separated at a separation mark arranged at the seconds ends. The package blanks may be fed onto the retaining means from a continuous tube blank provided on a reel, and fastened to the retaining means adjacent to the first openings on the outside of the respective walls of the package blanks. This method may lead to substantial waste of material, since the first ends are melted or welded to the retaining means and subsequently need to be cut off from the retaining means. This system may also lead to en expensive conversion and hence more expensive bags.
WO 2006/015447 A2 discloses an apparatus and method for forming and pre-filling packaging. A plastic film of packaging material, alternatively including preformed bags, wherein the adjacent bags are disposed in opposing relation to one another, is fed to filling and sealing stations. The plastic film, comprising the bags, is fed through a series of rollers to a supply exit, where the bags are received by carriages and transported to respective filling and sealing stations. The first bag is received by a first carriage in an up-right position and may be directly transported to its filling and sealing stations. The second bag must however be inverted before transportation to its respective filling and sealing station. After the bags have been filled and sealed they may be dropped onto a conveyor.
DE 32 34 877 A1 discloses a device and method for producing bags from a tube of plastic materials and filling these bags. The tube is fed by a roller and cut and welded at a lower end and then, at a predetermined distance from the lower end, cut at an upper end. The upper portion of the bag formed thereby may subsequently be held by a suction device. One portion of the suction device is moveable relative to the other, and hence may allow for the upper portion of bag to opened, while the lower, sealed portion is directed downwardly. The opened bag may be filled and sealed and finally dropped onto e.g. a conveyor. This document hence discloses a method where one bag at a time may be opened and filled.
There is a need for an alternative method for preparing package blanks, such as piping bags disclosed in WO 2005/115162 A1 for pre-filling of various foodstuff liquids.